Condenser



BEST AVAILABLE Com April 5, 1927a T. T. RODGERS ET AL CONDENSER Filed Sept. 24. 1924 Cl Bl I N 61 M014 My LEM lln

.1 lllllllll BEST AVAILABLE com Patented Apr. 5, 1927.

-"UNITED STATES PATENT OFFICE.

THOMAS 'r. RQDGERS, MARC A. GIBLIN, FRANCIS K. MOORE, AND GEORGE '1. MOORE, or I ,,MILWAUKEE, wrsconsm, assrenons TO nonssns RADIO conrona'rron, or wns'r ALLIS, wIs'coNsIN, A oonronsrron or WISCONSIN.

CONDENSER.

Our invention "has reference, in its broad aspect, to improvements in variable con-' densers of the'type wherein the dielectric medium is changedithroughthe instrumentallty of relatively adjustable opposed surfaces to 'afi'eot"capacity,--' and more particularly 1t isour rpurpose to-p'rovide means whereby the dielectric mediums of a plurality of such condensers-may be simultaneously variedby equal increments through the utilization of a'single'means; in the form of an axially movableactuating member connected to one of the condenserielements of each condenser unit. 4 ll -:-.In the "artrelating to improvements :in radio receivingap aratus of the type exemplified by multip e stage radio frequency amplification, efforts have been made to simplify'the process-of tuning'by'the utilization'of common means for manipulating the several rotors -0f-a--plurality of rotary condensersj'of thescdnventional type,-but in practice this andother. methods have been found impractical: for the reason that any slight inaccuracies or-distortion renders the system inope'rative.-..' On the other hand, we have "found'thatiby providing a common axiallymovable'lmeans to :which certain ele ments of our novel condensers-are connected, that the dielectricmediums of such con densers' may be ,varied by equal increments, thereby accomplishing the desired result:

Inpractice'we have found that excellent results and a high degree of selectivity can be attained by utilizin air dielectric condensers havingoppose condenser. surfaces for adjustment towardand away from each other in a common-plane, and to this end we have connected a movable element of each of our condensers to an axially adjustable common shaft, through the instrumentality of which all of the said elements-may be simultaneously affected to vary the dielectric mediums of-the respective condensers by equal increments. Furthermore, we have provided means whereby the opposing surfaces of our respective condensers may be adjusted independently, 'so that absolute accuracy of adjustment is attained, and in order to prevent possibility of variation in axial alignmentof our condenser elements, therebyaffecting capacity, we have formed one of the elements of each condenser of a greater diameter than its opposing element.

Application filed September 24,1924; Serial no. 739,491..

: The particular elements of our multiple condenser assembly employed to accomplish the" above and other objects attributed to it, will be hereinafter more fully described if in detail and specifically pointed out in the claims appended hereunto and forming a part of this specification.

"In the accompanying drawings wherein we have illustrated one of the preferred m:

bodiments of our invention The figure represents a vertical elevation of our-multiple condenser system with portions'=thereof broken away to more clearly show.the details. v

:Like characters of reference designate like or. similar parts throughout the several views of the drawings, in which .The numeral (1) designates generally a sectional shaft, the sections (2) of which i are connected together in axial alignment by studs (3). Interposed between each of the respective ends of the sections (2) of the shaft (1), is a disk, plate, or the like (4), the-same being provided with a central opening through which the stud (3) extends in assembly. Mounted upon fixed insulating bases (5), one opposed to each ofthe disks or plates l), are a plurality of similar disks, plates or the like (6). These disks or plates (6) are formed with enlarged centralxopenings (7), the peripheral edges of which are beveled for the purpose of reducing capacity, and -we have provided means in the form'of screws (8) for maintaining the plates (6) upon the respective insulating members. However, interposed between each plate and its adjacent insulating member is an inherently resilient member, such as a soft rubber washer (9). Manifestly, by manipulating the screws (8), the plates (6) are drawn down against the resiliency'of soft rubber washers (9) to accurately adjust the position of the same with respect to the plates (4). It will be understood that the plates (6) are supported on three-point contacts. While we have shown and described here means for individually adjusting but one of the plates, namely plate (6), it follows that the plate (4)? may also be adjusted by simply mounting uponthe shaft (1) a flanged'collar (not shown), to which the plate (4) may be adjustably secured through the instrumentality of screws, and the inherently resilient movement of the members (9) such as have justbeen described. In practice wediave found that by forming, the plate (6) of greater diameter than the plate (4), that variations in axial alignment will-be compensated for, which would otherwise produce variation in capacity. Of course, the plate (4:) could be made of greater diameter than the plate (6), andthe result would be the same.

lVe have shown here three condenser units, each of which is formed in the mani'ier described above, each-unit, consisting in .a.plate (4:) and a plate-(6), and ail-insulating-member (5),'but it will be understood that any number may be used and all are formed in the same manner.

The end of the shaft (1) is screw threaded as at (10), (preferably in the ratio fortyeight to the inch) and is engaged by an interiorly-screw threaded sleeve (11), carried by a rotatable dial member (12) mounted for movement upon any suitable support (13), such as a cabinet top. Thus, upon manipulation of the'dial- (12), the rotational sleeve (11) will be translated into proportional axial movement of the shaft. (1). This axial movement of the shaft willin turn move therespective plates (.4) toward or away from the plates (6), thereby varying-the dielectric medium between the plates 1) and (6) by equal increments. In-praetice such-variation of the movable plates of 'the condenser units will result'in the proper tuning of the various stages-of radio frequencyamplification, as in the-manner described in our present pending application for patent upon radio receiving apparatus, filed September 24th, 1924.

It has been indicated that the insulating members (5) are fixedly, mounted, and for this purpose a suitable frame, to which they. are attached, may be provided, -as-is here illustrated conventionally and designated-by the'numeral (14). Means in the form of a.-

spider (15) -is attached-to the frame and en' gages the end of the shaft to properly sup port the shaft in alignment,and theshaft is lockedagainst rotational movement by a detent (16) on-t-he spider working in a slot (17) in.the-shat't-, or in any other suitable i -men lrVhile it'is believed-that the operation of our invent-ion will be apparent from the. foregoing description, it ishere emphasized that in tuning a multiple stage radio frequency system to which our condenser assembly is applied, it is necessary to have butone tuning dial, here designated by (12) upon the manipulation of whichithe proper tuning of the respective stages of amplification is-iafi'ect-ed by means of proportional variation of the dielectric-mediums of the respective condensers-by axial movement-of the shaft (1). Thus a very much simplified 1,623,36 BEST AVAILABLE COP) multiple stage radio frequency amplification system is attained, the tuning of which should readily be accomplished by a person totally unfamiliar with the science of radio, or the manipulation of receiving sets, it simply being necessary to turn the dial until theproper station is found.

While in the foregoing there has been illustrated and described such combination and arrangement-ofelements as, constitute the preferred embodiments of our invention, it is nevertheless desired to emphasize the fact that interpretation of the invention should-only be-conclusive when-made in the light of the subjoined claims.

e claim 1. In-a multiple unit variable condenser system, a plurality of condensers each bemg formed with co-operating plates having normally opposed surfaces, inherently resilient means for adjusting certain of said co-operating plates, and a common axially movable member to which each of said other co-operating plates is connected formoving the same in the direction of the movementof the shaft to simultaneously vary the distances between the opposed surfaces of the plates of the respective condensers'by equal increments.

2. In amultiple unit variable condenser system, a plurality-of condensers each having a movable condenser element and a fixed condenser element, a sectional axially movable shaft, amovable condenser element being secured to-the-shaft between each of the respective -sections thereof, and all of said movable condenser elements adapted to be moved simultaneously and in: the direction ofthe movement of'the shaft upon manipulation thereofwhereby to vary the distances between the opposed surfaces of the condenser elementsaof each unit by equal increments. 1..

3.1'In1a multiple unit variable condenser system, a plurality of condensers each having a movable condenser element and'a-fixed condenser element, a sectionalaxially movable shaftextendingthrough all of the condenser elements; a movable eondenser element being secured-to the shaft'between each of the: respectivesections thereof, and all of thesaid movable condenser elements adapted-to bezmoved simultaneously and in the direction'of'the movement of the shaft upon manipulation thereof whereby to vary the distances .between the opposed surfaces of the condenser elements of each unit by equal increments.

In testimony whereof we afiix our signatures hereunto.

THOS. T. RODGERS. MARC A. GIBLIN. FRANCIS K. MOORE. GEORGE T. MOORE loo 

